MIPS: microMIPS: uasm: Add microMIPS micro assembler support.

Add new file 'uasm-micromips.c' that allows the micro assembler
to generate microMIPS ISA code. It can be included in the kernel
alongside the classic ISA as long as the platform supports the
microMIPS ISA.

Signed-off-by: Steven J. Hill <sjhill@mips.com>
Cc: linux-mips@linux-mips.org
Cc: cernekee@gmail.com
Cc: kevink@paralogos.com
Cc: ddaney.cavm@gmail.com
Patchwork: https://patchwork.linux-mips.org/patch/4923/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
(cherry picked from commit 5f011a866afbd03a5379f67f4e70e5efbdfc16e9)
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 51244bf..03de102 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -354,6 +354,7 @@
 	select SYS_SUPPORTS_BIG_ENDIAN
 	select SYS_SUPPORTS_LITTLE_ENDIAN
 	select SYS_SUPPORTS_SMARTMIPS
+	select SYS_SUPPORTS_MICROMIPS
 	select USB_ARCH_HAS_EHCI
 	select USB_EHCI_BIG_ENDIAN_DESC
 	select USB_EHCI_BIG_ENDIAN_MMIO
@@ -2102,6 +2103,9 @@
 config SYS_SUPPORTS_SMARTMIPS
 	bool
 
+config SYS_SUPPORTS_MICROMIPS
+	bool
+
 config ARCH_FLATMEM_ENABLE
 	def_bool y
 	depends on !NUMA && !CPU_LOONGSON2